1. Field of the Invention
The present invention relates to a structure for the placement of a head protecting air bag apparatus, and more particularly, to the structure for the placement of an air bag body of a head protecting air bag apparatus in which, at the time when a high load of a predetermined value or greater is applied to a vehicle side portion, gas is ejected from an inflator such that the air bag body expands into a curtain-like form so as to span over to the B pillar along a roof side rail due to the ejected gas. Here, "the air bag body expands so as to span over to the B pillar along the roof side rail" is intended to express a structure in which the air bag body expands from the A pillar or the C pillar to span over to the B pillar along the roof side rail, and also expresses a structure in which the air bag body expands, along the roof guide rail, from the A pillar and passes across the B pillar to extend to the C pillar.
2. Description of the Related Art
In order to improve the protection of the head of a vehicle occupant seated in the front seat when a high load of a predetermined value or greater is applied to a vehicle side portion, there have been proposed head protecting air bag apparatuses in which, an air bag body, which is stored in a folded state along a front pillar portion and a roof side rail portion, is inflated so as to expand into a curtain-like form. The structure of such a head protecting air bag apparatus is disclosed in International Publication No. WO 96/26087, and will be described hereinafter.
As shown in FIG. 16, the head protecting air bag apparatus 100 is mainly comprised of an elongated duct 106 which is disposed so as to extend from a front pillar portion 102 along a roof side rail 104, an air bag body 112 which is stored in the duct 106 in a folded state and which is fixed to the vehicle body at a front end fixing point 108 and a rear end fixing point 110, an inflator 116 which is connected to the rear end portion of the duct 106 by a hose 114 and which ejects gas at the time when a high load of a predetermined value or greater is applied to the vehicle side portion, and a belt-shaped strap 118 whose one end portion is fixed to the vehicle body and whose other end portion is fixed to the rear end portion of the air bag body 112. Further, the air bag body 112 is formed by connecting together a plurality of cells 120, each of which is formed in a substantially cylindrical shape whose longitudinal direction corresponds to the substantially vertical direction of the vehicle.
In accordance with the above-described structure, when a high load of a predetermined value or greater is applied to a vehicle side portion, gas is ejected from the inflator 116. The ejected gas flows into each of the cells 120 of the folded air bag body 112 via the hose 114 and the duct 106. Accordingly, each of the cells 120 is inflated so as to form a substantially cylindrical shape whose longitudinal direction substantially corresponds to the vertical direction of the vehicle. As a result, the air bag body 112 is inflated into a curtain-like form along a window glass 122.
However, in this structure for the placement of the head protecting air bag apparatus, the rear end portion of the air bag body 112 is located to the rear of a B pillar (the center pillar) portion 124 in the longitudinal direction of the vehicle, and is connected to the vehicle body by the strap 118. For this reason, it can be understood that, in some cases, the expanding air bag body 112 contacts the upper end portion of the garnish of the B pillar portion 124, enters into the gap between the garnish of the B pillar portion 124 and the vehicle body, and disturbs the expansion of the air bag body 112, thereby causing the garnish of the B pillar portion 124 to be displaced from the vehicle body.